Gustav Metzger used a photo of Jewish men scrubbing Viennese streets under the gaze of sneering Nazis to remind the world about antisemitism. The narrow defeat of Norbert Hofer proves his message is as relevant as ever

Using chilled velvet, tiny wood chips and turkey feathers, Wilson Bentley caused a flurry with his pioneering pictures of these miniature wonders. His results are astonishing – so why was he seen as an oddball outsider?